Gcc pads the size of an array using the alignment of its elements.

The size of the array may not be aligned according to alignment of its elements if an alignment attribute is
specified in a typedef. Fixes rdar://8665729 & http://llvm.org/PR5637.

llvm-svn: 130242

3 files changed, 39 insertions, 0 deletions

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index a31969dc907..e49bde3487e 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -724,6 +724,7 @@ ASTContext::getTypeInfo(const Type *T) const {
     std::pair<uint64_t, unsigned> EltInfo = getTypeInfo(CAT->getElementType());
     Width = EltInfo.first*CAT->getSize().getZExtValue();
     Align = EltInfo.second;
+    Width = llvm::RoundUpToAlignment(Width, Align);
     break;
   }
   case Type::ExtVector:
diff --git a/clang/test/Sema/align-x86-64.c b/clang/test/Sema/align-x86-64.c
index 6dcf5714b00..edea5d8b742 100644
--- a/clang/test/Sema/align-x86-64.c
+++ b/clang/test/Sema/align-x86-64.c
@@ -9,3 +9,17 @@ void foo(void) {
   char y[__alignof__(x) == 16 ? 1 : -1];
   frob(y);
 }
+
+// PR5637
+
+typedef __attribute__((aligned(16))) struct {
+  unsigned long long w[3];
+} UINT192;
+
+UINT192 ten2mk192M[] = {
+    {{0xcddd6e04c0592104ULL, 0x0fcf80dc33721d53ULL, 0xa7c5ac471b478423ULL}},
+    {{0xcddd6e04c0592104ULL, 0x0fcf80dc33721d53ULL, 0xa7c5ac471b478423ULL}},
+    {{0xcddd6e04c0592104ULL, 0x0fcf80dc33721d53ULL, 0xa7c5ac471b478423ULL}}
+};
+
+short chk1[sizeof(ten2mk192M) == 80 ? 1 : -1];
diff --git a/clang/test/Sema/align-x86.c b/clang/test/Sema/align-x86.c
index 0c84384305a..61bd1d33c9d 100644
--- a/clang/test/Sema/align-x86.c
+++ b/clang/test/Sema/align-x86.c
@@ -18,3 +18,27 @@ struct __attribute__((packed)) {unsigned int a;} g4;
 short chk1[__alignof__(g4) == 1 ? 1 : -1];
 short chk2[__alignof__(g4.a) == 1 ? 1 : -1];
 
+
+// PR5637
+
+#define ALIGNED(x) __attribute__((aligned(x)))
+
+typedef ALIGNED(2) struct {
+  char a[3];
+} T;
+
+short chk1[sizeof(T)       == 3 ? 1 : -1];
+short chk2[sizeof(T[1])    == 4 ? 1 : -1];
+short chk3[sizeof(T[2])    == 6 ? 1 : -1];
+short chk4[sizeof(T[2][1]) == 8 ? 1 : -1];
+short chk5[sizeof(T[1][2]) == 6 ? 1 : -1];
+
+typedef struct ALIGNED(2) {
+  char a[3];
+} T2;
+
+short chk1[sizeof(T2)       == 4 ? 1 : -1];
+short chk2[sizeof(T2[1])    == 4 ? 1 : -1];
+short chk3[sizeof(T2[2])    == 8 ? 1 : -1];
+short chk4[sizeof(T2[2][1]) == 8 ? 1 : -1];
+short chk5[sizeof(T2[1][2]) == 8 ? 1 : -1];